Difference between revisions of "En:Epimgconv"

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(19 10 2008 (version history))
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=Version history=
 
=Version history=
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19 10 2008: Pictures of any sizes between 1x1 and 8192x8192 are accepted; the internal compressor became faster and has somewhat better efficiency; Programs run also with EP64 (automatically compressed ones not yet). New parameters: -nointerp and -nocompress.
 +
 
07 06 2008: -color0-7, -bias parameters also can be given; if the .com file is >48K, it'll be compressed.
 
07 06 2008: -color0-7, -bias parameters also can be given; if the .com file is >48K, it'll be compressed.
  

Revision as of 10:24, 19 October 2008

The PC -> EP image converter program can be downloaded here. After unpacking (e.g with WinZip) it can be used in DOS prompt.

Using Epimgconv

An example for using it:

epimgconv foo.jpg foo.com

JPG, BMP, PNG, GIF and XPM input file formats are supported.

Parameters

Video mode can be chosen by -mode parameter, using the next values:

   * 0: 2 colours (black and white), normal vertical resolution
   * 1: 4 colours, normal függőleges felbontás
   * 2: 16 colours; a picture dithered to 256 colours is being converted into a picture of 16 colours without dither (default setting), normal függőleges felbontás
   * 3: 16 colours; it generates the same palette as mode 2 but the original picture is being dithered to 16 colours, normal függőleges felbontás
   * 4: 16 colours; it tries to mix generating palette and dithering but it's very slow, normal függőleges felbontás
   * 5: 256 colours, normal függőleges felbontás
   * 6: attribute mode, normal függőleges felbontás
   * 10: 2 colours (black and white), interlace
   * 11: 4 colours, interlace
   * 12: 16 colours; a picture dithered to 256 colours is being converted into a picture of 16 colours without dither, interlace
   * 13: 16 colours; it generates the same palette as mode 2 but the original picture is being dithered to 16 colours, interlace
   * 14: 16 colours; it tries to mix generating palette and dithering but it's very slow, interlace
   * 15: 256 colours, interlace
   * 16: attribute mode, interlace

So -mode 0-6 uses the normal függőleges felbontást and -mode 10-16 uses the interlace.


  • -raw 1 parameter enables to save in raw format, instead of the default .com application format; this way the size also can be larger (if the output format is application, size can be at maximum 46 characters * 288 lines only).
  • -size W H enables to set picture size. W = Width in characters, H = Height in (interlace: half image???félkép) lines.
  • As default, Epimgconv converts images into the largest possible size, but by using -scale X Y and -offset X Y parameters the image can be enlarged and offset.
  • -color0 ... -color7 parameters can set fix palette colours (actually setting of avoid using certain colours is not available).
  • -bias parameter sets fixbias - maybe better quality is availalble than with automatically selected colours. The colours can be given in #RGB format as well, e.g. #773 is white or #331 means bias=31.

If the .com file is too large (>48K), it'll be automatically compressed; so EXOS (being lucky) can load it though it starts much slowlier.


IstvanV

Suggestions, tips

I used the following methods and combined them:

  • attribute mode results the best quality and then the 4 colour mode;
  • I picked pictures containing not too complex structures;
  • I cut the better part from the picture but in the way that its composition remain pretty;
  • I looked for pictures where it's useful that there are lots of colours in the horizontally separated parts;
  • I picked pictures of strong colours and of many, diverse colours.

The better conversions were where these factors turned up the best way.


Endi

Version history

19 10 2008: Pictures of any sizes between 1x1 and 8192x8192 are accepted; the internal compressor became faster and has somewhat better efficiency; Programs run also with EP64 (automatically compressed ones not yet). New parameters: -nointerp and -nocompress.

07 06 2008: -color0-7, -bias parameters also can be given; if the .com file is >48K, it'll be compressed.

02 06 2008: Attribute and interlace mode options.

31 05 2008: First version, no attribute and interlace modes, only the black-and-white mode was with interlace.